Vaginosonographic Doppler velocimetry in both uterine arteries: elevated left-right differences and relationship to fetal haemodynamics and outcome.

Blood flow velocity was measured in both main stem uterine arteries by means of a transvaginally inserted Duplex scanner (240 degrees sector, pulsed Doppler) and visual vessel recognition to investigate normal and abnormal uterine perfusion. Its relationship to fetal circulation and fetal outcome was studied. Fetal vessels were investigated transabdominally. One hundred and seventy-six pregnancies with a high-risk for fetal malnutrition were examined between the 27th and the 40th week of gestation. In 113 (64%) patients we found normal uterine perfusion (A/B ratios in both uterine arteries less than 3, left-right difference less than 1) and in 63 (36%) cases the A/B ratios were outside our limits. A single abnormal A/B ratio in one of the uterine arteries or an abnormal left-right difference was classified as a mild form of abnormal uterine perfusion. Involvement of both uterine arteries was classified as a severe form. The severe form was associated with a higher frequency of pathological waveforms in fetal arteries and reduced fetal outcome. Clinically, velocimetry in both uterine arteries is of paramount importance when the degree of abnormal uterine perfusion is to be classified precisely.